Recently, with rapid development of an information society, a need for a flat panel display (FPD) having excellent properties such as slim thickness, light weight and low power consumption has been raised.
To meet this need, there has been developed image display panels such as a Liquid Crystal Display (LCD), a Plasma Display Panel (PDP), an Electroluminescent Display (ELD) and a Vacuum Fluorescent Display (VFD).
Among these panels, the LCD panel has been actively used for a notebook computer or a desktop monitor owing to its excellent resolution, color displaying ability and image quality.
Meanwhile, as the panels are enlarged according to customer demands, various processing facilities have been developed and facilities using new technologies have been developed.
In particular, an exposure apparatus is essential for forming patterns in each display panel, and performs a function that receives light from an illumination apparatus and transmits the light through a pattern of a photomask to image on a layer to be exposed, thereby exposing the layer.
FIG. 1 is a schematic sectional view illustrating a conventional exposure process. A light emitted from a light source 10 is irradiated to a photosensitive layer 30 on an upper portion of a substrate 40 according to patterns of a photomask 20 and thus the photosensitive layer 30 is exposed according to the pattern shape.
In this conventional exposure process, when an exposure area is a large area, a plurality of lighting devices is required to expose this large area. However, there is a problem in that a precise exposure process cannot be performed due to generation of a light intensity deviation between the lighting devices.